Accomplishments during the year: 1. Localizaton of rhomboid 1 and 4 determined.2. The sialic acid binding site has been modeled for BAEBL, identifying requirements for sialic acid binding. 3. The immune response to RH4 has been studied. This work continues to expand our understanding of parasite invasion of red cells by identifying the receptors and ligands and determining the potential of these targets for vaccine development. We show that recombinant P. falciparum RH 4 can block invasion but antibodies to PfRH4 cannot block invasion.